Time-resolved spectroscopic and electrophysiological data reveal insights in the gating mechanism of anion channelrhodopsin.

ABSTRACT: Channelrhodopsins are widely used in optogenetic applications. High photocurrents and low current inactivation levels are desirable. Two parallel photocycles evoked by different retinal conformations cause cation-conducting channelrhodopsin-2 (CrChR2) inactivation: one with efficient conductivity; one with low conductivity. Given the longer half-life of the low conducting photocycle intermediates, which accumulate under continuous illumination, resulting in a largely reduced photocurrent. Here, we demonstrate that for channelrhodopsin-1 of the cryptophyte Guillardia theta (GtACR1), the highly conducting C = N-anti-photocycle was the sole operating cycle using time-resolved step-scan FTIR spectroscopy. The correlation between our spectroscopic measurements and previously reported electrophy

SUBMITTER: Dreier MA 

PROVIDER: S-EPMC8121809 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature